Implement attach_light

Author: BruceSherwood

labextension/vpython/src/glowcommlab.js

@@ -444,7 +444,7 @@ function control_handler(obj) {  // button, menu, slider, radio, checkbox, winpu
 }
 
 // attrs are X in {'a': '23X....'} avaiable: none
-var attrs = {'a':'pos', 'b':'up', 'c':'color', 'd':'trail_color', // don't use single and double quotes; available: comma, but maybe that would cause trouble
+let attrs = {'a':'pos', 'b':'up', 'c':'color', 'd':'trail_color', // don't use single and double quotes; available: comma, but maybe that would cause trouble
          'e':'ambient', 'f':'axis', 'g':'size', 'h':'origin', 'i':'textcolor',
          'j':'direction', 'k':'linecolor', 'l':'bumpaxis', 'm':'dot_color',
          'n':'foreground', 'o':'background', 'p':'ray', 'E':'center', '#':'forward', '+':'resizable',
@@ -471,35 +471,35 @@ var attrs = {'a':'pos', 'b':'up', 'c':'color', 'd':'trail_color', // don't use s
          '?':'font', '/':'texture'}
 
 // attrsb are X in {'b': '23X....'}; ran out of easily typable one-character codes
-var attrsb = {'a':'userzoom', 'b':'userspin', 'c':'range', 'd':'autoscale', 'e':'fov',
+let attrsb = {'a':'userzoom', 'b':'userspin', 'c':'range', 'd':'autoscale', 'e':'fov',
               'f':'normal', 'g':'data', 'h':'checked', 'i':'disabled', 'j':'selected',
               'k':'vertical', 'l':'min', 'm':'max', 'n':'step', 'o':'value',
               'p':'left', 'q':'right', 'r':'top', 's':'bottom', 't':'_cloneid',
               'u':'logx', 'v':'logy', 'w':'dot', 'x':'dot_radius', 
               'y':'markers', 'z':'legend', 'A':'label','B':'delta', 'C':'marker_color',
               'D':'size_units', 'E':'userpan', 'F':'scroll', 'G':'choices', 'H':'depth',
-			  'I':'round', 'J':'name'}
+			  'I':'round', 'J':'name', 'K':'offset'}
 
 // methods are X in {'m': '23X....'} available: u
-var methods = {'a':'select', 'b':'pos', 'c':'start', 'd':'stop', 'f':'clear', // unused eghijklmnopvxyzCDFAB
+let methods = {'a':'select', 'b':'pos', 'c':'start', 'd':'stop', 'f':'clear', // unused eghijklmnopvxyzCDFAB
 			   'q':'plot', 's':'add_to_trail',
                't':'follow', 'w':'clear_trail',
                'G':'bind', 'H':'unbind', 'I':'waitfor', 'J':'pause', 'K':'pick', 'L':'GSprint',
 		       'M':'delete', 'N':'capture'}
 
-var vecattrs = ['pos', 'up', 'color', 'trail_color', 'axis', 'size', 'origin', 
+let vecattrs = ['pos', 'up', 'color', 'trail_color', 'axis', 'size', 'origin', 
                 'direction', 'linecolor', 'bumpaxis', 'dot_color', 'ambient', 'add_to_trail', 'textcolor',
                 'foreground', 'background', 'ray', 'ambient', 'center', 'forward', 'normal',
-                'marker_color']
+                'marker_color', 'offset']
 
-var textattrs = ['text', 'align', 'caption', 'title', 'title_align', 'xtitle', 'ytitle', 'selected', 'capture', 'name',
+let textattrs = ['text', 'align', 'caption', 'title', 'title_align', 'xtitle', 'ytitle', 'selected', 'capture', 'name',
                  'label', 'append_to_caption', 'append_to_title', 'bind', 'unbind', 'pause', 'GSprint', 'choices']
 
 // patt gets idx and attr code; vpatt gets x,y,z of a vector            
-var patt = /(\d+)(.)(.*)/
-var vpatt = /([^,]*),([^,]*),(.*)/
-var quadpatt = /([^,]*),([^,]*),(.*)/
-var plotpatt = /([^,]*),([^,]*)/
+const patt = /(\d+)(.)(.*)/
+const vpatt = /([^,]*),([^,]*),(.*)/
+const quadpatt = /([^,]*),([^,]*),(.*)/
+const plotpatt = /([^,]*),([^,]*)/
 
 function decode(data) { 
     "use strict";
@@ -511,12 +511,12 @@ function decode(data) {
 	var ms = []
 
 	if ('attrs' in data) {
-		var c = data['attrs']
+		let c = data['attrs']
 		for (i=0; i<c.length; i++) { // step through the encoded attributes and methods
-			var d = c[i]
+			let d = c[i]
 			// constructor or appendcmd not currently compressed
-			var whichlist = d[0] // 'a' or 'b' or 'm'
-			var datatype = (whichlist == 'm') ? 'method' : 'attr'
+			let whichlist = d[0] // 'a' or 'b' or 'm'
+			let datatype = (whichlist == 'm') ? 'method' : 'attr'
 			s = d.slice(1)
 			m = s.match(patt)
 			idx = Number(m[1])
@@ -623,7 +623,8 @@ function handler(data) {
 	}
 	*/
 
-
+	
+	
 	if (data.cmds !== undefined && data.cmds.length > 0) handle_cmds(data.cmds)
 	if (data.methods !== undefined && data.methods.length > 0) handle_methods(data.methods)
 	if (data.attrs !== undefined && data.attrs.length > 0) handle_attrs(data.attrs)
@@ -650,7 +651,7 @@ function handle_cmds(dcmds) {
 		var vlst = ['pos', 'color', 'size', 'axis', 'up', 'direction', 'center', 'forward', 'foreground',
 				 'background', 'ambient', 'linecolor', 'dot_color', 'trail_color', 'textcolor', 'attrval',
 				 'origin', 'normal', 'bumpaxis','texpos', 'start_face_color', 'end_face_color', 'marker_color',
-				 'start_normal', 'end_normal']
+				 'start_normal', 'end_normal', 'offset']
 		if ((obj != 'gcurve') && ( obj != 'gdots' ) ) vlst.push( 'size' )
 		var cfg = {}
 		var objects = []
@@ -804,7 +805,15 @@ function handle_cmds(dcmds) {
 				}
 				break
 			}
-			case 'local_light':   {glowObjs[idx] = local_light(cfg); break}
+			case 'local_light': {
+				let g = glowObjs[idx] = local_light(cfg)
+				console.log(g)
+				if (cfg.offset !== undefined) { // mocking up attach_light
+					g.__obj = glowObjs[cfg.attach_idx]
+					g.canvas.attached_lights.push(g)
+				}
+				break
+			}
 			case 'distant_light': {glowObjs[idx] = distant_light(cfg); break}
 			case 'canvas':        {
 				if ((typeof isjupyterlab_vpython !== 'undefined') && (isjupyterlab_vpython === true)) {
@@ -904,12 +913,12 @@ function handle_cmds(dcmds) {
 async function handle_methods(dmeth) {
     "use strict";
 	//console.log('METHODS')
-	for (var idmeth=0; idmeth<dmeth.length; idmeth++) { // methods; cmd is ['idx':idx, 'attr':method, 'val':val]
-		var cmd = dmeth[idmeth]
-		var idx = cmd.idx
-		var method = cmd.attr
-		var val = cmd.val
-		var obj = glowObjs[idx]
+	for (let idmeth=0; idmeth<dmeth.length; idmeth++) { // methods; cmd is ['idx':idx, 'attr':method, 'val':val]
+		let cmd = dmeth[idmeth]
+		let idx = cmd.idx
+		let method = cmd.attr
+		let val = cmd.val
+		let obj = glowObjs[idx]
 
 		if (method == 'GSprint') {
 			GSprint(val)
@@ -923,17 +932,17 @@ async function handle_methods(dmeth) {
 		} else if (method === 'add_to_trail') {
 			obj['_func'] = val
 		} else if (method === 'bind') {
-			var evts = val.split(' ')
-			for (var evt in evts) {
-				var e = evts[evt]
+			let evts = val.split(' ')
+			for (let evt in evts) {
+				let e = evts[evt]
 				if (binds.indexOf(e) == -1) 
 					throw new Error('There is no error type "'+e+'"')
 			}
 			obj.bind(val, process_binding)
 		} else if (method === 'unbind') {
-			var evts = val.split(' ')
-			for (var evt in evts) {
-				var e = evts[evt]
+			let evts = val.split(' ')
+			for (let evt in evts) {
+				let e = evts[evt]
 				if (binds.indexOf(e) == -1) 
 					throw new Error('There is no error type "'+e+'"')
 			}
@@ -973,17 +982,17 @@ async function handle_methods(dmeth) {
 function handle_attrs(dattrs) {
     "use strict";
 	//console.log('ATTRS')
-	for (var idattrs=0; idattrs<dattrs.length; idattrs++) { // attributes; cmd is {'idx':idx, 'attr':attr, 'val':val}
-		var cmd = dattrs[idattrs]
-		var idx = cmd.idx
-		var obj = glowObjs[idx]
-		var attr = cmd['attr']
-		var val = cmd['val']
-		var triangle_quad = ['v0', 'v1', 'v2', 'v3']
+	for (let idattrs=0; idattrs<dattrs.length; idattrs++) { // attributes; cmd is {'idx':idx, 'attr':attr, 'val':val}
+		let cmd = dattrs[idattrs]
+		let idx = cmd.idx
+		let obj = glowObjs[idx]
+		let attr = cmd['attr']
+		let val = cmd['val']
+		let triangle_quad = ['v0', 'v1', 'v2', 'v3']
 		if (val instanceof vec) {
 			if (attr === 'pos' && (obj instanceof points || obj instanceof curve)) {
-				var ptlist = []
-				for (var kk = 0; kk < val.length; kk++) {
+				let ptlist = []
+				for (let kk = 0; kk < val.length; kk++) {
 					ptlist.push( val[kk] )
 				}
 				obj[attr] = ptlist

vpython/vpython.py

@@ -18,7 +18,7 @@
 
 # List of names that will be imported from this file with import *
 __all__ = ['Camera', 'GlowWidget', 'version', 'GSversion', 'Mouse', 'arrow', 'attach_arrow',
-           'attach_trail', 'baseObj', 'box', 'bumpmaps', 'button',
+           'attach_light', 'attach_trail', 'baseObj', 'box', 'bumpmaps', 'button',
            'canvas', 'checkbox', 'clock', 'color', 'combin', 'compound', 'cone', 'controls',
            'curve', 'curveMethods', 'cylinder', 'distant_light', 'ellipsoid',
            'event_return', 'extrusion', 'faces', 'frame', 'gcurve', 'gdots',
@@ -98,7 +98,7 @@
           'logx':'u', 'logy':'v', 'dot':'w', 'dot_radius':'x',
           'markers':'y', 'legend':'z', 'label':'A', 'delta':'B', 'marker_color':'C',
           'size_units':'D', 'userpan':'E', 'scroll':'F', 'choices':'G', 'depth':'H',
-          'round':'I', 'name':'J'}
+          'round':'I', 'name':'J', 'offset':'K', 'L':'attach_idx'}
 
 # methods are X in {'m': '23X....'}
 # pos is normally updated as an attribute, but for interval-based trails, it is updated (multiply) as a method
@@ -111,7 +111,7 @@
 __vecattrs = ['pos', 'up', 'color', 'trail_color', 'axis', 'size', 'origin', 
             'direction', 'linecolor', 'bumpaxis', 'dot_color', 'ambient', 'add_to_trail',
             'foreground', 'background', 'ray', 'ambient', 'center', 'forward', 'normal',
-            'marker_color']
+            'marker_color', 'offset']
 
 __textattrs = ['text', 'align', 'caption', 'title', 'xtitle', 'ytitle', 'selected', 'label', 'capture', 'name',
                  'append_to_caption', 'append_to_title', 'bind', 'unbind', 'pause', 'GSprint', 'choices']
@@ -208,6 +208,7 @@ def empty(cls):
 
     @classmethod
     def handle_attach(cls): # called when about to send data to the browser
+
         ## update every attach_arrow if relevant vector has changed
         for aa in cls.attach_arrows:
             if not aa._run: continue
@@ -524,9 +525,9 @@ class standardAttributes(baseObj):
                          ['visible', 'xoffset', 'yoffset', 'font', 'height', 'opacity',
                            'border', 'line', 'box', 'space', 'align', 'linewidth', 'pixel_pos'],
                          ['text']],
-                 'local_light':[['pos', 'color'],
+                 'local_light':[['pos', 'color', 'offset'],
                          [],
-                         ['visible'],
+                         ['visible', 'attach_idx'],
                          []],
                  'distant_light':[['direction', 'color'],
                          [],
@@ -617,6 +618,8 @@ def setup(self, args):
         self._size_units = 'pixels'
         self._texture = None
         self._pickable = True
+        self._offset = vector(0,0,0)
+        self._attach_idx = None
         self._save_oldaxis = None # used in linking axis and up
         self._save_oldup = None # used in linking axis and up
         _special_clone = None
@@ -1390,6 +1393,23 @@ def attach_arrow(o, attr, **args): # factory function returns arrow with special
               _last_val=vector(134.472, 789.472, 465.472), _last_pos=vector(134.472, 789.472, 465.472))
     baseObj.attach_arrows.append(a)
     return a
+    
+def attach_light(o, **args): # factory function returns local_light with special attributes
+    '''
+    The object "o" will have a local_light attached with options "offset" and "color".
+    The local_light will constantly be positioned at o.pos plus the offset.
+    '''
+    if not isinstance(o.pos, vector): raise AttributeError("Cannot attach a light to an object that has no pos attribute.")
+    if 'color' in args:
+        if not isinstance(args['color'], vector): raise AttributeError("The color attribute must be a vector.")
+    else:
+        args['color'] = o.color # default color
+    if 'offset' in args:
+        if not isinstance(args['offset'], vector): raise AttributeError('The attach_light attribute "offset" must be a vector.')
+    else:
+        args['offset'] = vector(0,0,0) # default offset
+    a = local_light(pos=o.pos+args['offset'], attach_idx=o.idx, color=args['color'], offset=args['offset'])
+    return a
 
 class attach_trail(standardAttributes):
     def __init__(self, obj, **args):
@@ -3350,6 +3370,24 @@ def __init__(self, **args):
         if (canvas.get_selected() is not None):
             canvas.get_selected()._lights.append(self)
 
+    @property
+    def offset(self):
+        return self._offset
+    @offset.setter
+    def offset(self, value):
+        self._offset = vector(value)
+        if not self._constructing:
+            self.addattr('offset')
+
+    @property
+    def attach_idx(self):
+        return self._attach_idx
+    @attach_idx.setter
+    def attach_idx(self, value):
+        self._attach_idx = vector(value)
+        if not self._constructing:
+            self.addattr('attach_idx')
+
 class distant_light(standardAttributes):
     def __init__(self, **args):
         args['_default_size'] = vector(1,1,1)